JP2008110679A - Automotive bumper reinforcement - Google Patents

Abstract

An object of the present invention is to provide a bumper reinforcement for an automobile that is crushed and deformed at the time of a collision and that effectively exhibits an impact mitigating effect.
In a bumper reinforcement 1 attached to a side member 5 via an impact mitigating member 2 provided at the tip of left and right side members 5 extending in the front-rear direction of the automobile, the bumper reinforcement 1 has an impact. A hole 3 as an easily deformable means is provided in the vicinity of the coupling part 1d with the relaxation member 2, and the hole 3 forming portion of the bumper reinforcement 1 and the shock relaxation member 2 are provided at the time of a vehicle collision, particularly at a low-speed offset collision. Thus, the impact energy is absorbed to reduce the impact and the deformation of the side member 5 is suppressed.
[Selection] Figure 2

Description

  The present invention relates to a bumper reinforcement for an automobile, and more particularly, to a bumper reinforcement that is crushed and deformed at the time of a vehicle collision to mitigate the impact.

  2. Description of the Related Art Conventionally, a bumper of an automobile includes a bumper reinforcement having a hollow closed cross-section structure extending in the vehicle width direction, a pad material (bumper absorber) provided along the bumper reinforcement, and a bumper cover made of a synthetic resin covering these. .

  FIG. 7 is a schematic plan view of a conventional general front bumper and a member supporting the front bumper. The front ends of the left and right front side members 5 provided in the engine room and extending in the front-rear direction can be crushed and deformed by an impact at the time of collision. A shock absorbing member (crash box) 2 is attached, and a bumper reinforcement 1 is attached to the front end of the front side member 5 via the shock absorbing member 2.

  The bumper reinforcement 1 is formed with inclined end portions 1b that are gently bent from the central portion 1a and extend obliquely rearward and outward from the left and right sides of the central portion 1a that extends linearly along the vehicle width direction. The rear surfaces of the left and right inclined end portions 1b are coupled to the left and right impact relaxation members 2. 7, 50 is a suspension member provided between the front and rear intermediate portions of the left and right side members 5, 51 is a left and right suspension tower, 52 is provided between the front portions of both side members, and is a radiator located in front of the engine room. It is a radiator support lower that supports the lower edge. In FIG. 7, 60 is a bumper cover, and 61 is a pad material.

  In the conventional bumper reinforcement 1, when one inclined end portion 1b collides with the rigid wall T at a low speed (for example, about 15 km / h), the impact mitigating member 2 is caused by the action of the collision load as shown in FIG. Although it is crushed and deformed in the axial direction, the inclined end portion 1b may remain almost without being crushed. Particularly in recent years, bumper reinforcement formed by extrusion molding of light metals such as aluminum has been used to reduce weight, and this kind of bumper reinforcement is less likely to be crushed because it is thicker than a thin steel plate. If the inclined end portion 1b is not crushed and deformed even if the impact mitigating member 2 is crushed, the impact mitigating effect is not exhibited effectively, and the front side member 5 is crushed and deformed in the axial direction even at a low speed collision.

  Generally, when repairing a vehicle body at a low-speed collision, it is only necessary to replace the bumper reinforcement 1 and the impact mitigation member 2 with new ones. However, if the front side member 5 which is a skeleton member of the vehicle body is crushed and deformed, it is replaced. However, it is difficult to fix the crushing while pulling from the front, but it is a large-scale repair work and requires a lot of work.

  Therefore, as a conventional structure for efficiently mitigating impact by bumper reinforcement at the time of collision, for example, as described in Patent Document 1 below, the lateral width is used to support the bumper reinforcement of the rear bumper at the tip of the side member. It is proposed to support the bumper reinforcement over a wide range in the vehicle width direction using a wide bumper stay. According to this, in the event of a collision, the bumper reinforcement is crushed and deformed over a wide range in the vehicle width direction between the collision partner and the bumper stay so as to reduce the impact.

However, in the front bumper, since the lower edge of the radiator is disposed between the bumper reinforcement at the front and rear positions and the radiator support lower, it is difficult to provide a wide bumper stay. In addition, this type of bumper stay supports the bumper reinforcement in a wide range at the time of a collision and causes the bumper reinforcement to be crushed and deformed. Low, it was difficult to demonstrate the overall impact mitigation performance of the bumper reinforcement and bumper stay.
JP 2004-182139 A

  SUMMARY OF THE INVENTION Accordingly, the present invention provides a bumper reinforcement in which the impact mitigating effect of the bumper reinforcement is effectively exhibited in combination with the impact mitigating effect of the impact mitigating member provided at the tip of the side member that supports the bumper reinforcement. Is made as an issue.

  The present invention is a bumper reinforcement having a hollow closed cross-section structure extending in the vehicle width direction of an automobile, and can reduce impact by crushing and deforming at the tip of left and right side members extending in the front-rear direction of the vehicle at the time of a vehicle collision. In the bumper reinforcement of an automobile, which is provided with an impact mitigating member and attached to the front ends of the left and right impact mitigating members by connecting the back, the bumper reinforcement has a position in the vicinity of the joint with the impact mitigating member, Easily deforming means for crushing and deforming the bumper reinforcement due to the impact at the time of collision is provided. The bumper reinforcement itself at the time of the offset collision is also crushed and deformed near the impact mitigating member by the easily deformable means, and the impact mitigating member is also crushed and deformed to exert a high impact mitigating effect. Does not lead to deformation.

  The bumper reinforcement has a square hollow closed cross-sectional shape, and as the easily deformable means, the bumper reinforcement is located slightly closer to the center in the vehicle width direction than the joint portion between the bumper reinforcement and the shock absorbing member. Is provided in the vertical direction (Claim 2). The formation of the hole is suitable as an easily deformable means.

  The bumper reinforcement is formed with an inclined end portion that is bent from both left and right ends of a linear center portion along the vehicle width direction and extends obliquely toward the rear rear vehicle side, and the back surface of the inclined end portion is formed on the impact reducing member. Combine with. The punched hole penetrating the inclined end portion in the vertical direction is formed at a position between the bent portion at both ends of the central portion and the joint portion of the impact relaxation member. The inclined end portion is crushed and deformed by the formation of the punched hole.

  As the easily deformable means, at the time of a collision, it protrudes from the surface portion of the bumper reinforcement at a position facing the joint portion between the bumper reinforcement and the impact mitigating member or a position slightly closer to the center in the vehicle width direction than the joint portion. A protrusion that hits the collision partner is provided before the surface portion. Since the collision load concentrates on the protrusion during the collision and the vicinity of the bumper reinforcement protrusion is crushed and deformed, the protrusion is suitable as an easily deformable means.

  The protrusion is formed of a hard solid member having a substantially triangular shape in plan view, which is a member different from the bumper reinforcement (Claim 5). Since the protrusion is a hard member, the bumper reinforcement is easily crushed and deformed during a collision.

  A first embodiment of a bumper reinforcement to which the present invention is applied will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, a pair of front side members (hereinafter simply referred to as side members) 5 and 5 which are frame members of a vehicle body extending in the front-rear direction are provided on the left and right sides of the engine room. Between the left and right side members 5, 5, a suspension member 50 is installed in the vehicle width direction at the front-rear intermediate position, and a suspension tower 51, on the upper surface of each side member 5, 5 is slightly behind the suspension member 50. 51 is provided. As in the conventional structure, a radiator support lower (see 52 in FIG. 7) is provided between the front lower surfaces of the side members 5 and 5 in the vehicle width direction.

  The front end of each of the left and right side members 5 and 5 is provided with impact mitigating members 2 and 2, respectively. 1).

  As shown in FIGS. 1 and 2, the impact relaxation member 2 is formed in a box shape with a hollow closed cross section made of a metal plate, and the height and width of the outer shape match the front end of the side member 5 and the side. The member 5 is provided so as to extend forward. The impact mitigating member 2 is made of a thick plate formed so as to close the rear end thereof and formed wider than the main body of the shock absorbing member 2 into a wide plate 55 made of a thick plate closing the front end of the side member 5. The two plate members 20 and 55 are fastened together by bolt members and are joined to the front end of the side member 5.

  The front surface of the impact mitigating member 2 is closed by a front plate 22, and bolt members 23 projecting forward for mounting the reinforcement 1 are provided on the front plate 22 at two locations, the upper half and the lower half. It is.

  The impact relaxation member 2 is provided with a plurality of easily deformable portions 21 formed of shallow V-shaped grooves or the like on the outer peripheral surface at predetermined intervals in the axial direction. The impact relaxation member 2 is crushed and deformed in the axial direction at the time of a vehicle collision. It is easy.

  The reinforcement 1 is a long member formed by extrusion molding of a light metal, for example, aluminum, and has a square closed cross-sectional structure including an upper surface portion 11, a bottom surface portion 12, a front surface portion 13, and a rear surface portion 14. Eggplant. In the reinforcement 1, a reinforcing portion 15 that divides the inside of the closed cross section vertically is integrally formed over the entire length of the reinforcement 1. The thicknesses of the front and rear surface portions 11, 12, 13, 14 and the reinforcing portion 15 are formed to be about 2.5 mm.

  The reinforcement 1 includes a linear center portion 1a and an inclined end portion 1b that gently bends from both ends of the center portion 1a and extends obliquely toward the rear vehicle exterior. The bent portions 1 c at both ends of the central portion 1 a are located inside the left and right side members 5, and the inclined portion 1 b extends to the outside of the left and right side members 5.

  In the reinforcement 1, the inclined end portions 1b on both the left and right sides are respectively coupled to the impact relaxation members 2 on the front ends of the left and right side members 5. Bolt through holes (16, see FIG. 4) are formed in the rear surface portion 14 of the inclined end portion 1b at positions corresponding to the bolt members 23 of the impact relaxation member 2, respectively. A service hole 17 penetrating the front surface portion 13 is formed in front of these bolt through holes.

  The reinforcement 1 is a state in which the bolt member 23 of the impact reducing member 2 is passed through the bolt through hole 16 of the inclined end portion 1b, and the rear surface portion 14 of the inclined end portion 1b and the front surface of the impact reducing member 2 are overlapped. Then, the nut member is fastened to the bolt member 23 from the service hole 17, and the inclined end portion 1 b of the reinforcement 1 is fastened to the impact mitigating member 2.

  On the inclined end portion 1 b side of the reinforcement 1, a plurality of holes 3 that are easy-to-deform means are formed so that the reinforcement 1 is easily crushed and deformed when the vehicle collides. Three holes 3 are formed in a range S between the bent portion 1c of the central portion 1a and the connecting portion 1d between the inclined end portion 1b and the impact relaxation member 2, and each of the hole 3 has an upper surface portion 11. The reinforcing portion 15 and the bottom surface portion 12 are provided so as to penetrate in a vertical direction. The diameter of the hole 3 is about 30 mm at the largest and about 20 mm at the smallest.

  The reinforcement 1 includes a thick pad material 61 on the front side of the front surface portion 13 and is covered with a synthetic resin bumper cover 60 integrally with the pad material 61 to constitute a front bumper.

  As shown in FIGS. 2 and 3, the reinforcement 1 is configured such that when one of the inclined end portions 1 b collides with a rigid wall T that is substantially parallel to the inclined end portion 1 b due to a low-speed offset collision of the vehicle. Since the rigidity of the range S in which the hole 3 is formed is lower than that of other parts, the periphery of the coupling portion 1d is crushed rearward around the range S, thereby absorbing the collision energy. The collision energy that could not be absorbed by this is absorbed by the crushing deformation of the impact relaxation member 2.

  In this way, the reinforcement 1 itself and the impact mitigating member 2 are crushed, so that the collision energy at the time of low-speed collision is almost completely absorbed and the impact is mitigated and the side member 5 is not deformed. Accordingly, for repairing the automobile, the reinforcement 1 and the impact mitigation member 2 may be replaced with new ones, and these are fixed with a fastening structure using a bolt member. No repair work is required.

  Note that the reinforcement 1 is crushed and deformed even during high-speed collision, and has an impact mitigating action. In the reinforcement 1, the central portion 1 a comes into contact with a collision partner at the time of a frontal collision of the vehicle, but the central portion 1 a side is crushed and deformed starting from the range S provided with the punched hole 3, and exhibits an impact mitigating action. To do.

  In the present embodiment, the reinforcement 1 is provided with the punched hole 3 on the vehicle inner side than the connecting portion 1d of the inclined end portion 1b with the impact mitigating member 2. If it is provided on the outer side, the end of the inclined end portion 1b on the outer side will be bent rearward from the hole 3 and the impact mitigating effect cannot be expected when a portion on the vehicle outer side than the coupling portion 1d hits the collision partner. is there.

  In the present embodiment, three punched holes 3 are formed. However, the present invention is not limited to this, and the size and number of the punched holes may be changed in consideration of the amount of crushing deformation with respect to the collision speed. Further, the present invention may be applied not only to a front bumper of an automobile but also to a reinforcement of a rear bumper.

  Next, another embodiment of the present invention will be described with reference to FIGS. The basic structure such as reinforcement, impact mitigating member and side member, and the mounting structure are the same as those of the previous embodiment, and different points will be mainly described. In the drawings, the same members are denoted by the same reference numerals. As shown in FIGS. 4 and 5, the inclined end portion 1 b of the reinforcement 1 includes a joint portion between the inclined end portion 1 b and the shock absorbing member 2 from a bent portion 1 c between the central portion 1 a and the inclined end portion 1 b. On the front surface portion 13 in the range S between 1d, a protrusion 4 is installed as an easily deformable means protruding forward.

  The protrusion 4 is made of a solid aluminum member having a substantially triangular shape close to a right triangle in plan view, and the thickness of the member is about 20 mm. The protrusion 4 has a base 41 overlapped with the front surface 13 of the reinforcement 1, a front side 43 forms an inclined surface that rises toward the outside of the vehicle, and a side 42 on the outside of the vehicle has a width of the impact reducing member 2. It is arranged so that it is positioned in the middle of the direction or slightly inside the vehicle.

  The projection 4 is formed with thin coupling flanges 45 and 46 projecting from the upper edge and the lower edge in the vertical direction, and the coupling flanges 45 and 46 together with the base 41 are attached to the front surface portion 13 of the inclined end portion 1b. Etc. are firmly bonded. The pad material 61 provided on the front side of the reinforcement 1 is formed with a recess 611 that avoids the protrusion 4 at a position facing the protrusion 4, and the protrusion 4 is fitted into this. The reinforcement 1 and the pad material 61 are integrally covered with a bumper cover 60.

  As shown in FIGS. 5 and 6, at the time of a low-speed offset collision of the vehicle, the projection 4 hits the collision partner (rigid wall) T, and the collision load acts on the projection 4 intensively, so that the projection 4 mounting portion of the inclined portion 1b And the peripheral part is pushed in by the hard protrusion 4, is crushed and deformed, and the collision energy is absorbed, and there is an effect similar to that of the first embodiment.

  The protrusions may be substantially semicircular or quadrangular in plan view, but the protrusions have a substantially right triangle shape in plan view where the protruding apex is at the center in the width direction of the shock absorbing member 2 or slightly inside the vehicle. Since the collision load can be concentratedly applied to a narrow range of the reinforcement 1, the reinforcement 1 can be efficiently crushed, which is preferable.

It is a schematic perspective view which shows the bumper reinforcement of the 1st Embodiment of this invention, and the member by the side of the vehicle body which supports this. It is a principal part top view of the said bumper reinforcement. It is a schematic plan view which shows the deformation | transformation state at the time of the low-speed offset collision of the said bumper reinforcement. It is a principal part expansion perspective view of the bumper reinforcement which shows the 2nd Embodiment of this invention. It is a principal part top view of the bumper reinforcement of 2nd Embodiment. It is a schematic plan view which shows the deformation | transformation state at the time of the low-speed offset collision of the bumper reinforcement of 2nd Embodiment. It is a schematic plan view which shows the conventional bumper reinforcement and the member by the side of the vehicle body which supports this. It is a schematic plan view which shows the deformation | transformation state at the time of the low-speed offset collision of the conventional bumper reinforcement.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bumper reinforcement 1a Center part 1b Inclined edge part 11 Upper surface part 12 Bottom face part 18 Bending part 19 Coupling part 2 Impact relaxation member 3 Punching hole (easy deformation means)
4 Protrusion (easy deformation means)

Claims (5)

A bumper reinforcement having a hollow closed cross-sectional structure extending in the vehicle width direction of an automobile, and having an impact mitigating member capable of mitigating impact by being crushed and deformed at the time of a vehicle collision at the front ends of left and right side members extending in the longitudinal direction of the vehicle In the bumper reinforcement of an automobile, which is installed and attached to the tip of the left and right impact mitigating members with the back
A bumper reinforcement provided in the bumper reinforcement is provided with an easily deforming means for crushing and deforming the bumper reinforcement by an impact at the time of a collision at a position in the vicinity of the joint portion with the impact reducing member. . The bumper reinforcement of the vehicle according to claim 1,
The bumper reinforcement is a square hollow closed cross-sectional shape,
As the easily deformable means, a bumper reinforcement of an automobile provided with a punching hole penetrating the bumper reinforcement in the vertical direction at a position slightly closer to the center in the vehicle width direction than the joint portion between the bumper reinforcement and the impact mitigation member. Forcement. In the bumper reinforcement of the vehicle according to claim 2,
The bumper reinforcement is formed with an inclined end portion that is bent from both left and right ends of a linear center portion along the vehicle width direction and extends obliquely toward the rear rear vehicle side, and the back surface of the inclined end portion is formed on the impact reducing member. None to join with,
A bumper reinforcement for an automobile in which the punched hole penetrating the inclined end portion in the vertical direction is formed at a position between a bent portion at both ends of the central portion and a joint portion of the impact relaxation member. In the bumper reinforcement of the vehicle according to claim 1,
As the easily deformable means, at the time of a collision, it protrudes from the surface portion of the bumper reinforcement at a position facing the joint portion between the bumper reinforcement and the impact mitigating member or a position slightly closer to the center in the vehicle width direction than the joint portion. A bumper reinforcement for automobiles provided with a projection that hits the collision partner before the surface portion. The bumper reinforcement of an automobile according to claim 4,
A bumper reinforcement for an automobile in which the protrusion is formed of a hard solid member having a substantially triangular shape in plan view, which is a member different from the bumper reinforcement.